Mathematics · Permutations and Combinations

JEE Main 2025 — 29 January, Morning Shift — Question 68

The number of 6 -letter words, with or without meaning, that can be formed using the letters of the word MATHS

such that any letter that appears in the word must appear at least twice, is 4 \qquad

Answer: 1405

Numerical answer — enter this value.

Step-by-step solution

(i) Single letter is used , then no. of words =5=5

(ii) Two distinct letters are used, then no. of words5C2×(6!2!4!×2+6!3!3!)=10(30+20)=500{ }^{5} \mathrm{C}_{2} \times\left(\frac{6!}{2!4!} \times 2+\frac{6!}{3!3!}\right)=10(30+20)=500

(iii) Three distinct letters are used, then no. of words

5C3×6!2!2!2!=900{ }^{5} \mathrm{C}_{3} \times \frac{6!}{2!2!2!}=900

Total no. of words =1405=1405

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Subject
Mathematics
Chapter
Permutations and Combinations
Topic
Problems based on both permutations and combinations
The number of 6 -letter words, with or without meaning, that can be… | JEE Main 2025 PYQ with Solution · DhiX AI